I don’t know any female furry or animal UTAU with a full English VB.
If you’re OK with Non-Japanese VB with some extra English samples then I suggest my own UTAU Lychee.
She has Finnish VB with some extra English consonants recorded. Finnish has 8 vowels, so IMO decent Engrish is little easier with her than a reqular JP VBs but it still needs lot of work and random phoneme improvise to make sound really good.
Here is a sample that I made her singing in Engrish:
https://twitter.com/xingtuxue/status/969998681809260545?s=21
EDIT: It's possible to combine her Finnish VB with her normal JP CVVC because that VB has surffix. You can use らりるれろ sound do make that "dd sound" like "bu
tter" in American English or use Japanese "u" phoneme instead Finnish one
<s>Finnish "u" can sound too "Spanish" and for some odd reasons Japanese "u" sounds more accurate for English</s>
All Lychee's VBs are downloadable here